On his first day back in office, President Donald Trump signed 26 executive orders on Jan. 20. Among them was the "Protecting the Meaning and Value of American Citizenship" order, which stated that children born in the United States to parents who are not legal or permanent residents should not be considered U.S. citizens.But according to a recent study by the Migration Policy Institute (MPI) and Penn State University's Population Research Institute, eliminating birthright citizenship would increase—not decrease—the number of unauthorized individuals living in the United States in the long run.